Air conditioning unit



June l, 1943. R, w. KRrrzL-:R 2,320,525

AIR CONDITIONIVNG UNIT Filed Aug. 6, 1941 'Patented June 1, 1943 UNITED STATI-:s PATENTl ori-ICE asznszs Ara CONDITIONING UNIT melma W. Kram, chicago, nl.

Application August 6, 1941, Serial No. 405,593

(ci. x2-14o) 6 Claims.

Y The invention relates to air conditioning units.

. One object of the invention is to provide aunit which includes an evaporating or cooling coil and' improved means for removing the condensate which drips from the coil, so that odors thereof and the moisture therein will not permeate the space or room in which the unit is used.

This object is attained primarily by providing an automatically controlled electric heating element for vaporizing the condensate and carrying oil the steam through an exhaust pipe and discharging it outside of the building in which the air conditioning unit is used.

Other objects of the invention will appear from the detailed description.

The invention consists in the several novel features which are hereinafter set forth and are more particularly defined by claims at the conclusion hereof.

In the drawing: Fig. 1 is a vertical section oi an air conditioning unit embodying the invention. Fig. 2 is a section of the device for heating and vaporizing the condensate for discharge through the exhaust pipe. Fig. 3 is a diagram of the electrical connections for the electric heating element and i'or the electric motor which drives the fan.

The invention is exempliiled in a unit in which the ian for circulating the air and the evaporating coil are contained in a housing which is adapted to be secured on a 'ceiling for conditioning the air in a room or other space.

The unit comprises a housing built up of a top-plate I and a depending shell il which is secured to the top-plate Ill by screws. The shell has a cylindrical portion provided with discharge openings i2 for the air and a bottom-wall i3 which has a central air inlet I. The evaporator comprises a coll of pipe l5 which is connected by branchpipes i5', lib to a refrigerating unit in any manner as well understood in the art. A fan Il disposed in opening l in the bottom II is driven by an electric motor i1 which is secured to the underside of and supported from thetop-plate l0 of the housing. 'Ihe fan I6 draws air through the central opening in the bottom of the housing and forces it into contact with the evaporator by which the air is removed. The cooled air is discharged through the openings il of the housing.

The bottom-wall I3 extends inwardly and is inclined downwardly from the side-wall Il and has an upturned inner edge or nange Il around the inlet-opening l to form a/bowl or well in the housing for catching and retaining the condensate from the coil Il. The deepest portion of the bowl is located adjacent the flange I4 so that the condensate will ilow toward said flange and inwardly of the coil II.

In practice it has been found that frost frequently accumulates on the evaporator coil and periodically melts so the .condensate gravitates to the bottom I3 of the housing and flows to and accumulates in the annular pocket around the flange I4. If it is permitted to remain so it will be absorbed by the conditioned air, it fouls the air and produces an unpleasant oder. It also increases the humidity of the air. The invention provides for heating the condensate to form steam and carrying oif the steam to the outside of thebuilding or room in which the unit is used. An electric heater or resistance element 20 of any suitable-construction is provided. This heater is in the form of a coil and disposed in a vertical pipe 2|. 'I'he lower end of the pipe 2i has a flared or funicular portion 22 which extends to a point adjacent the bottom of the bowl and the level of the condensate when it accumulates on the bottom i3. Pipe 2l is surrounded by a sleeve of insulating material 23 to coniine the heat produced by heater 2|) to the pipe 2i and keep it away from the chamber within the housing through which the air is forced while it is being conditioned. Pipe 2i is extended vthrough the ceiling and is connected by a horizontal pipe-section 24 to a suitable point of discharge for the vapor or steam usually outside of the building and away from the space to which the conditioned air is delivered. One end of the resistance-coil oi the heater 20 is connected by a conductor 25 to one of the'line-conductors 26 and its other end is connected to a contact-strip 21 which is supported from said coil. A conductor 28, which is connected to the other line conductor` 20* is connected to a contact-strip 30 which is insulated from and supported from the funicular portion 22 oi' pipe 2l. The lower ends of contact-strips 21 and 30 terminate adjacent the lowest portion of bottom i3 of the housing `Where they will be submerged in the condensate when it accumulates. When any appreciable amount ofcondensate accumulates in the center of the housing and condensate will form an electrical path between contact-strips 2l, 30 and close a circuit to energize the heating coil 20. The motor I1 is also connected to line conductor 28 and in parallel with the heating element.

In the operation of the unit the fan I8 will be driven by the motor Il, draw air into the housing through inlet 9, force air around the evaporator-coil I5 and discharge the cooled air through the openings I2 of the housing. When a suflicient column or condensate accumulates to submerge the contact-strips 21, 30, a circuit through the heating coil will be automatically closed through line conductor 26, conductor 25, coil 20 and contact-strip' 21, the condensate, contact-strip 30, conductor 28, and line-conductor 26. The coil 20 will then -be energized to produce sufilcient heat in the pipe 2l and its extension 22 to vaporize the condensate. The steam produced will be directed by the extension 22 to ilow upwardly through pipe 2| and so that it will be discharged through pipe-section 24 where desired. This construction functions as a flue for removing the foul vapor from the condensate from the housing so that it will not intermingle with the air which is circulated in the room around the housing. When the condensate has been reduced below the level of the lower end of contact-strips 21, 30, the circuit through the coil will be automatically interrupted at said strips. During the vaporization and removal of the condensate the insulating sleeve 23 will prevent heat transfer from the pipe 2| to the chamber in the housing. I The circuit for the heating coil and the motor I1 are connected in parallel to the line conductors so that the heater will be operative through, and can be controlled by, the control device for the motor.

The invention exemplifies an air conditioning unit which is equipped with an automatically controlled electric heating unit for removal of the condensate.

stricted to the details set forth, since these may .be modified within the scope of the appended claims, without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent is:

1. In an air conditioning unit, the combination with a housing provided with an inlet and an outlet for air, an evaporator ior cooling the air in the housing, and a motor-driven fan assoelated with the housing and for forcing air therethrough, of means for retaining condensate from the evaporator in the housing, an electric heating element for vaporizing the condensate in the retaining means, means for` automatically controlling the actuation of the heating element by the condensate in the retaining means, a conduit for conducting the vapor through the housing, and means for insulating the conduit to prevent heat transfer to the air flowing through the housing.

2. In an air conditioning unit, the combination with a housing provided with an inlet and an outlet for air, an evaporator for cooling the air in the housing, and a motor-driven fan associated with the housing and -for forcing airtherethrough, of means in the bottom of the housing for retaining condensate from the evaporator, an electric heating element for vaporizing the condensate'in the retaining means, a pipe around the heating element for conducting the vapor through the housing provided with insulating` means for preventing heat transfer from the element to the chamber in the housing containing the evaporator, an electric circuit for the heatand means for carrying the vapor from the pipe and away from the casing.

3. In an air conditioning unitrthe combination with a housing provided with an inlet and an outlet for air, an evaporator for cooling the air in the housing, and a motor-driven fan associated with the housing and for forcing air therethrough, of means in the bottom of the housing for retaining condensate from the evaporator, an electric heating element for-vaporizing the condensate in the retaining means, a pipe around the heating element for carrying vapor through the housing, provided with an insulating sleeve for preventing heat transfer from the element to the chamber in the housing containing the evaporator, a -ilared terminal on the lower end of the pipe, an electric circuit for controlling the heating element, and contacts in the iiared terminal, connected v to the circuit, and adapted to be connected to close the circuit by the condensate in the retaining means.

4. In an air conditioning unit, the combination with a housing provided with an inlet and outlet for air, an evaporator in the housing for cooling the air, and a motor-driven fan associated with the housing for circulating air through the housing and around the evaporator. the housing being provided with a bottom adapted to retain condensate from the evaporator, of an electric heating element in the housing for vaporizing the condensate on the -bottom of the housing, a ilue for conducting the vaporized condensate from the bottom and through the housing and removing it separately from the air circulated around the evaporator, and means for automatically controlling the actuation of the heating by the condensate on the bottom of the housing.

5. In an air conditioning unit, the combination-with a housing provided with an inlet and outlet for air, an evaporator in the housing for cooling the air, and a motor-driven fan associated with the housing for circulating air through the housing and around the evaporator, the housing being provided with a bottom adapted to retain condensate from the evaporator, of an electric heating c-oil in the housing for vaporlzing the condensate on the bottom of the housing, a flue around the heating coil, for conducting the vapor-ized condensate from the bottom and through the housing and removing it separately from the air circulated around the evaporator, and means for automatically controlling the actuation of the heating by the condensate on the bottom of the housing.

6. In an air conditioning unit, the combination with a housing provided with an inlet and outlet for air, an evaporator in the housing for cooling the air, and a motor-driven fan assoclated with the housing for circulating air through the housing and around the evaporator, the housing being provided with a bottom adapted to retain condensate from the evaporator of an electric heating. element in the housing for vaporlzing the condensate on the bottom of the housing, an upwardly extending pipe having a flared intake at its lower end for conducting the vaporized condensate from the bottom and through the housing and removing it separately from the air circulated around the evaporator, and means for automatically controlling the actuation of the heating by the condensate on the bottom of the housing.v l

RICHARD W. KRITZER. 

